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71.
This paper focuses on the design problem of a memoryless state feedback robust H-infinity controller for a class of uncertain neutral systems. By using a newly established integral inequality, a new delay-dependent bounded real lemma for such systems is derived without involving a fixed model transformation. Furthermore, new delay-dependent sufficient conditions for the existence of robust H-infinity controllers are presented in terms of nonlinear matrix inequalities. A design procedure involving an iterative algorithm is also proposed to design such controllers. Numerical examples are given to demonstrate the less conservatism of the proposed method. 相似文献
72.
信息技术安全评价标准的现状和发展 总被引:5,自引:2,他引:3
讨论信息技术安全评价的标准的现状和发展,介绍世界各国制订的主要 标准的特点,重点分析信息技术安全评价标准的最新发展-ISO15408,简称CC标准。 相似文献
73.
Graeme Ritchie 《Minds and Machines》2007,17(1):67-99
Over recent decades there has been a growing interest in the question of whether computer programs are capable of genuinely
creative activity. Although this notion can be explored as a purely philosophical debate, an alternative perspective is to
consider what aspects of the behaviour of a program might be noted or measured in order to arrive at an empirically supported
judgement that creativity has occurred. We sketch out, in general abstract terms, what goes on when a potentially creative
program is constructed and run, and list some of the relationships (for example, between input and output) which might contribute
to a decision about creativity. Specifically, we list a number of criteria which might indicate interesting properties of
a program’s behaviour, from the perspective of possible creativity. We go on to review some ways in which these criteria have
been applied to actual implementations, and some possible improvements to this way of assessing creativity.
相似文献
Graeme RitchieEmail: |
74.
Franco Raimondi Charles Pecheur Guillaume Brat 《Electronic Notes in Theoretical Computer Science》2007,190(2):113
We address the problem of verifying planning domains as used in model-based planning, for example in space missions. We propose a methodology for testing flight rules of planning domains which is self-contained, in the sense that flight rules are verified using a planner and no external tools are required. We review and analyse coverage conditions for requirements-based testing, and we reason in detail on "Unique First Cause" (UFC) coverage for test suites. We characterise flight rules using patterns, encoded using LTL, and we provide UFC coverage for them. We then present a translation of LTL formulae into planning goals, and illustrate our approach on a case study. 相似文献
75.
76.
文章从建立BtoC电子商务标准的必要性着手,指出了目前国内相关网站存在的普遍问题,分析了国外B toC电子商务标准的不足之处,对建立适合我国自己的标准进行了探讨。 相似文献
77.
A mixed integer linear model for selecting the best decision making unit (DMU) in data envelopment analysis (DEA) has recently been proposed by Foroughi [Foroughi, A. A. (2011a). A new mixed integer linear model for selecting the best decision making units in data envelopment analysis. Computers and Industrial Engineering, 60(4), 550–554], which involves many unnecessary constraints and requires specifying an assurance region (AR) for input weights and output weights, respectively. Its selection of the best DMU is easy to be affected by outliers and may sometimes be incorrect. To avoid these drawbacks, this paper proposes three alternative mixed integer linear programming (MILP) models for identifying the most efficient DMU under different returns to scales, which contain only essential constraints and decision variables and are much simpler and more succinct than Foroughi’s. The proposed alternative MILP models can make full use of input and output information without the need of specifying any assurance regions for input and output weights to avoid zero weights, can make correct selections without being affected by outliers, and are of significant importance to the decision makers whose concerns are not DMU ranking, but the correct selection of the most efficient DMU. The potential applications of the proposed alternative MILP models and their effectiveness are illustrated with four numerical examples. 相似文献
78.
通过有限元计算和试验,探讨了垫条宽度对混凝土劈裂抗拉试验的影响.结果表明:当垫条宽度与立方体试件边长的比值k在0.167~0.600时,有效缓解了加载部位的应力集中,能保证立方体试件在端面中心处起裂. 相似文献
79.
利用数列频率测度的概念及其性质,讨论了一类带有正负系数的非线性偏差分方程,得到了此类偏差分方程的频密振动性准则.仅利用方程系数数列的水平集"频率测度"的概念,给出了偏差分方程解的频密振动的充分条件,并且准确刻画了解的振动频率. 相似文献
80.
针对波浪数值水池研究现状,提出了长峰不规则波数值波浪水池研究亟待解决的3个问题:海浪谱的拓展、波能衰减机理讨论及长峰不规则波数值模拟精度评价标准.基于黏性数值波浪水池技术,以文氏海浪谱为目标谱,对深水长峰不规则波进行了数值模拟;分析了数值模拟中波能衰减的主要原因,并提出了基于优化网格生成和离散格式的减小衰减的方法;根据《水面船模耐波性试验规程》对数值模拟结果进行了误差计算,并提出了适用于不规则波数值模拟评价标准的建议. 相似文献